The Happy Birthday greeting is one of the most widely recognised songs in the world, traditionally sung at parties, family gatherings and classroom celebrations whenever candles are lit. Its simple melody and familiar words make it instantly understood across ages and languages, which is why short clips of it are reused so often in online videos, memes and birthday messages. Creators keep returning to it because it needs no explanation: a few seconds are enough to signal a birthday, a surprise and a moment of good wishes.